Design And Implementation Of Visual Developing Tool Of Digital Set-Top Box

The digital television is developing very quickly in recent years. When facing the increasing domestic set-top boxes market, how to develop software of Set-Top Box to meet the customers'needs in the shortest time, using the lowest manpower and costs, is the first problem the software developers should consider if they want to occupy the market. During the traditional set-top box software development, the development of User Interface takes up about half of the entire work. Therefore, developing a visual developing tool of digital Set-Top Box is crucial for developing low-cost set-top box software rapidly.The visual developing tool has two important features: visual development and good portability of the generated codes. On the basis of the set-top box software architecture, a portable set-top boxes graphics interface system was designed. A visual developing tool based on it includes a human-computer interaction tool and a middle layer. The middle layer ensures the easy-portability of the codes generated by the visual developing tool, including resource data structures, the operating system abstraction layer, graphics and the state machine engine. Set-top box interface system is an event-driven software system, so one of the key technologies in developing visual tool is the design of the state machine engine. Most set-top boxes use eight-bit bitmaps in order to save storage space, therefore, the generation of 256-color palette is a key point of the visual developing tools to ensure the"What You See Is What You Get"features. On the other hand, the code editor and code generator are also key parts. A state machine engine for the visual developing tool was designed based on the improvement of the traditional one. According to the features of graphical user interface system and the visual characteristics of human's eyes, an algorithm about the generation of 256-color palette was designed. After the design of key data structures of visual developing tool, a code editor was constructed on the basis of flex and bison, finally the problem of the code generation was settled.A graphical interface system has been developed by the visual developing tool and tested on three different Set-Top Box platforms: STi5162, STi7109 and LSI2005. The results show that the display efficiency of UI is good, the state machine runs normally, the basic function of code editor and code generator has been completed, and the basic function of visual development and easy-portability of generated codes has been completed.